LINK BETWEEN HEART AND BRAIN IN PATIENTS AFFECTED BY ATRIAL FIBRILLATION: ASSOCIATIONS OF CARDIC MORPHOLOGICAL CHANGES AND CEREBROVASCULAR LESION LOAD. DATA FROM THE STRAT-AF 2 STUDY.

ABSTRACT: Background: Atrial Fibrillation (AF) is the most common and clinically relevant cardiac arrythmia, with high risk of ischemic stroke and mortality. Beyond ischemic stroke, neurological complications of AF are more numerous and more complex than hypothesized, causing a blending of clinical manifestations such as cognitive impairment, motor disability and depression. Neuroimaging examination of patients with AF, have revealed a significant cerebrovascular lesion load with an unexpected high prevalence of several markers of cerebral small vessel disease (cSVD), in addition to the well-known cardioembolic infarcts. CSVD has been recognized as the potential pathological substrate of all neurological manifestations in AFpatients. However, pathogenetic mechanisms relating AF and cSVD are still not clear. Considering the main role of cardiac dysfunction in the development and maintenance of the arrythmia, there is a growing interest in studying the interactions between cardiac structural abnormalities with neuroimaging cSVD markers. However, limited studies have indagated the associations between cardiac structural changes and cerebrovascular load in patients with a diagnosis of AF. Principal aims: In this study, in a cohort of elderly AF-patients on oral anticoagulants we aimed to: 1. Describe frequency and prevalence of all features of cerebrovascular damage (either microangiopathic and non-microangiopathic) and cardiac structural changes. 2. Examine associations and correlations between cerebral non-microangiopathic and microangiopathic markers of cerebrovascular damage, and cardiac morphological features. Methods: This is a cross sectional-analysis of preliminary data derived from the Strat-AF 2 study. It is an observational, prospective, single center hospital based study conceived as the longitudinal extension of the previously Strat-AF 1, aimed at evaluating the role of biological markers both circulating and imaging-based, for cerebral bleeding risk stratification in patients with AF on OACs, referring to Centre for Thrombosis of Careggi. From March 2021 to June 2022, we consecutive enrolled elderly patients (>65 years old), with a diagnosis of AF and on OAC in primary and secondary prevention for thromboembolism. All patients underwent a comprehensive clinical assessment and neuroimaging (CT scan or MRI) and cardiological (echocardiography) examination. A small sub-group of patients also underwent cardiac-MRI. Main results: One hundred seventy-nine patients (mean age 78.6±6.7 years old), with a slightly higher male prevalence (58%), were considered for the neuroimaging examination: 100 patients underwent MRI, while 79 patients underwent CT scan. Among the patients belonging to the MRI cohort, 65 also underwent cardiac MRI. High prevalence of cSVD markers and cardiac structural changes, mainly atria dilatation, were found in our cohort. Moreover, left chambers changes (left atrial dilatation and left ventricle hypertrophy) appeared significantly and independently associated with the presence of higher burden of small vessel disease Markers (cerebral atrophy and lacunes). To the best of our knowledge, this is the first study carried out on the association between cardiac parameters and neuroimaging burden of microangiopathic and non-Microangiopathic features in patients with a long story of AF and without a required diagnosis of previous ischemic stroke. Despite several limitations of this study, our findings could be a little hint into the complex association existing between cardiac morphological changes and cSVD in AF-patients. Further studies with a larger sample size and a longitudinal design are needed to better determine these associations.